A building entrance protector, i.e. junction box, provides an interface for cables from the central office of the service provider for distribution to subscribers throughout the building served by the junction box. A typical building entrance protector contains a protector field and a plurality of connectors for interconnection. The protector field provides surge protection with five-pin plug-in protectors for each subscriber's line.
The protector field comprises a panel having sockets thereon for receiving plug-in protectors, which are solid state devices printed on wiring board. A typical protector field has a five by five grid configuration. Due to the need to conserve space within a junction box, the twenty-five plug-in protectors are placed abutting each other on the panel.
A typical five-pin plug-in protector has a rectangular box shape housing measuring 3/4 inch wide, 1/2 inch high and 15/8 inch long. Extending from one end of the protector are five terminals and from the opposite end is an integral tab handle having the height of the protector.
A typical plug-in protector has five terminals. Three of the five terminals are longer and are connected to the solid state surge protective device within the housing. The remaining two shorter terminals are for connection to the subscriber's line. Different length terminals allow a service technician to unplug the two shorter terminals while keeping the longer terminals in the sockets in order to service or discontinue service of a particular subscriber's line while safely maintaining surge protection on the line.
Typical plug-in protectors used for telephone lines in a prior art panel do not meet the high category (HiCAT) standard for crosstalk because the protectors are plugged closely adjacent to each other. Crosstalk is the undesirable signal from one protector that interferes with the signal of an adjacent protector caused by electromagnetic coupling. Crosstalk increases with higher frequencies. Therefore, a protector panel designed for lower frequency application is not suitable for high category frequency applications such as Category 3 (CAT3), Category 4 (CAT4) and Category 5 (CAT5) standards. Regular telephone lines fall within the Category 3 standard and the prior art panel may be used. However, such a prior art panel would not be suitable for protectors in the Category 5 standard, which has a critical (maximum) frequency of 100 megahertz (MHz).
Because crosstalk is caused by electromagnetic coupling, a direct enhancement in minimizing or eliminating crosstalk is to increase the distance between adjacent protectors. However, separation of adjacent protectors is space consuming and therefore expensive as each building entrance protector would accommodate less protectors, requiring additional building entrance protectors and space at the location.
Therefore, there is a need of a protector field panel that provides optimum positioning of five-pin plug-in protectors to minimize crosstalk between adjacent protectors while conserving space.